chuck hagel at defense, john brennan at the cia, and now senator mccain saying he is not ready to call it a day on all of this. a congress hearing -- >> then you ought to have your facts straight. >> reporter: after congressional hearing. >> who responsible then? >> reporter: republican senator john mccain challenge, the white house on its response to benghazi. now he is going further on nbc's "meet the press." >> so there are many, many questions and we have had a massive cover-up. >> a cover-up of what? i'm just saying you, a cover-up of what? >> i'll be glad to send you a list of questions that have not been answered. >> reporter: the white house says it's given answers. conducted 20 briefings for congress. officials have testified at ten hearings, answered how queries. it all adds up to 10,000 pages of documents. just last week, mccain himself told cnn recent responses on benghazi were, quote, adequate. so, is this just politics? when we asked mccain's office what other questions the senator still had, we were referred to this january press release, listing 14 questions. like this